It is known to form an ornamental line pattern on a resinous display panel of an indicating instrument such as by printing. For example, the line pattern forms a hair line figure having plural parallel lines or circles concentric with a rotation axis of a pointer of the indicating instrument. Alternatively, the line pattern is designed to radially extend from the rotation axis, like the rays of the sun.
This kind of ornamental line pattern is formed to improve an appearance of the resinous display panel. However, the appearance of the conventional resinous panel having such an ornamental line pattern is likely to be lower than an appearance of a metal panel.
Generally, appearance is based on a sense of human sight. Therefore, it is generally difficult to directly apply a quality appearance such as a metal-like appearance to design parameters for designing the line pattern. Also, there is no disclosure about design parameters for improving the metal-like appearance with the line pattern.